While bored recently, I decided to take apart a few old pieces of electronic equipment and attempt to reverse-engineer them. I've been doing pretty well, but I've come to an IC that I can identify but doesn't seem to exist on the manufacturer's website.
Specifically, it's an SOP20 package marked "I87-0205-000 1202S7E", with Microchip's logo on it. I'm fairly new to this, but context clues (looking at the board) suggest that this is some kind of MCU, which makes sense, given the manufacturer. I've tried googling these numbers, and while I get about 8 billion results on Alibaba with vendors willing to sell me hundreds of them, none of them actually tell me what it is, or offer any datasheets. I've tried contacting a few of these vendors asking for datasheets, but none have gotten back to me yet.
So, anecdotes aside, are there any good methods of figuring out the name of a chip/finding the datasheet for a somewhat unidentifiable chip?
Best Answer
You've pretty much got the process down.
Recognize that some parts, such as mask-programmed microcontrollers and perhaps some pre-programmed flash microcontrollers may be house numbered, which means they have a part number assigned by the customer, not the manufacturer, and no information will be forthcoming from the latter, nor will you likely ever find a datasheet. The part may or may not be basically a standard part.
Sometimes, especially with microcontrollers, you can match the package, manufacturer (if known) and the pin pattern (things like power pins, crystal pins, etc.) to reduce the number of options, but it's not an especially rewarding exercise unless you're being paid to analyze someone else's product. The magic is all in the firmware in such cases, and it will be copyright (as well as hardware locked, though that doesn't slow down some unethical folks much).